[Glitch] Use the new JSX transform everywhere

Port 8f66126b10 to glitch-soc

app/javascript/flavours/glitch/features/blocks/index.jsx

@@ -1,4 +1,3 @@
-import React from 'react';
 import { connect } from 'react-redux';
 import ImmutablePropTypes from 'react-immutable-proptypes';
 import { debounce } from 'lodash';